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In 1983, General Motors Corporation (GM) petitioned the National Highway Traffic Safety Administration (NHTSA) to allow the use of the biofidelic Hybrid III midsize adult male dummy as an alternate test device for FMVSS 208 compliance testing of frontal impact, passive restraint systems. To support their petition, GM made public to the international automotive community the limit values that they imposed on the Hybrid III measurements, which were called Injury Assessment Reference Values (IARVs). During the past 20 years, these IARVs have been updated based on relevant biomechanical studies that have been published and scaled to provide IARVs for the Hybrid III and CRABI families of frontal impact dummies. Limit values have also been developed for the biofidelic side impact dummies, BioSID, ES-2 and SID-IIs.

The development of the WorldSID 50th percentile male dummy was initiated in 1997 by the International Organization for Standardization (ISO/SC12/TC22/WG5) with the objective of developing a more biofidelic side impact dummy and supporting the adoption of a harmonized dummy into regulations. More than 45 organizations from all around the world have contributed to this effort including governmental agencies, research institutes, car manufacturers and dummy manufacturers. The first production version of the WorldSID 50th male dummy was released in March 2004 and demonstrated an improved biofidelity over existing side impact dummies. Full-scale vehicle tests covering a wide range of side impact test procedures were performed worldwide with the WorldSID dummy. However, the vehicle safety performance could not be assessed due to lack of injury risk curves for this dummy. The development of these curves was initiated in 2004 within the framework of ISO/SC12/TC22/WG6 (Injury criteria).

Neck injury assessment is part of the FMVSS208 requirements. Hardware tests are often conducted to validate whether the vehicle safety system meets the requirements. This paper presents a full vehicle finite element model using LS-DYNA, including structural components, restraint system components, and dummies. In the case of a frontal impact at 30deg angle, in the areas of neck compression, neck extension and neck kinematics, it is demonstrated that a good correlation is achieved between the response of a FE dummy in the model and those of ATDs in the physical hardware tests. It is concluded that the math tool may be applied to comprehend test and design variations that may arise throughout a vehicle development lifecycle and to help develop a vehicle restraint system.

The complexity of vehicle-pedestrian collisions necessitates extensive validation of pedestrian computational models. While body components can be individually simulated, overall validation of human pedestrian models requires full-scale testing with post mortem human surrogates (PMHS). This paper presents the development of a full-scale pedestrian impact test plan and experimental design that will be used to perform PMHS tests to validate human pedestrian models. The test plan and experimental design is developed based on the analysis of a combination of literature review, multi-body modeling, and epidemiologic studies. The proposed system has proven effective in testing an anthropometrically correct rescue dummy in multiple instances. The success of these tests suggests the potential for success in a full-scale pedestrian impact test using a PMHS.

Panic braking can cause an “in-position” unbelted occupant to become “out-of-position.” Although the braking event dynamics and initial positioning of the occupant affect the final position at time of impact (if any), general trends are assumed. FMVSS208 now includes “out-of-position” (OOP) performance for Anthropomorphic Test Devices (ATDs) sizes twelve month to six year-old. Airbag suppression technologies currently address that range of OOP occupants. The objective of this study is to develop an approach to defining OOP test positions for the recently released 10 year old ATD and to assist restraint engineers in developing strategies to help reduce the risk of inflation induced injury to the larger out-of-position child. A series of panic brake tests was conducted with the 10 year-old Hybrid III to study panic braking kinematics. Antilock braking (ABS) generated the desired constant deceleration from high initial speeds (40 to 60mph) in three types of vehicles.

In 1983, General Motors Corporation (GM) petitioned the National Highway Traffic Safety Administration (NHTSA) to allow the use of the biofidelic Hybrid III midsize adult male dummy as an alternate test device for FMVSS 208 compliance testing of frontal impact, passive restraint systems. To support their petition, GM made public to the international automotive community the limit values that they imposed on the Hybrid III measurements, which were called Injury Assessment Reference Values (IARVs). During the past 20 years, these IARVs have been updated based on relevant biomechanical studies that have been published and scaled to provide IARVs for the Hybrid III and CRABI families of frontal impact dummies. Limit values have also been developed for the biofidelic side impact dummies, BioSID, EuroSID2 and SID-IIs.

This paper deals with the multi-parameter and boundary mannequin techniques in creating human models in automotive applications. The concepts and applications of single-parameter, multiple parameter and boundary mannequin method are discussed respectively to clarify certain confusion. Emphasis is put on how to create boundary mannequins for a specific application, which may have been puzzling many engineers in practical applications. The authors would like to share their experience in using the digital human modeling software and make discussions on some common issues. A number of case studies from typical automotive manufacturing assembly operations are also presented to demonstrate the usage of the multi-parameter and boundary mannequin techniques.

It is commonly known that in an automotive manufacturing assembly line several workers perform either a common task or a number of different tasks simultaneously, and there is a need to represent such a multi-worker operation realistically in a digital environment. In the past years, most digital human modeling applications were limited only in a single worker case. This paper presents how to simulate multi-worker operations in a digital workcell. To establish an effective communication and interaction between the mannequins, some existing commercial software package has provided a digital input/output mechanism. The motion for each mannequin is often programmed independently, but can be interrupted anytime by the other digital human models or devices via a communication channel.

In 1998, Rouhana et al. described development of a new device, called the IR-TRACC (InfraRed - Telescoping Rod for Assessment of Chest Compression). In its original concept, the IR-TRACC uses two infrared LEDs inside of a telescoping rod to measure deflection. One LED serves as a light transmitter and the other as a light receiver. The output from the receiver LED is converted to a linear function of chest compression using an analog circuit. Tests have been performed with IR-TRACC units at various labs around the world since 1998. A first-generation IR-TRACC system was retrofit into a Q3 dummy by TNO. Similarly, a mid sized male Hybrid III dummy thorax and a small female Hybrid III dummy thorax have been designed by First Technology Safety Systems (FTSS) such that each contains 4 second-generation IR-TRACC units. The second-generation IR-TRACC is the result of continued development by FTSS, especially in the areas of the analysis circuit, manufacturing and calibration methods.

The Hybrid III family of dummies is used to estimate the response of an occupant during a crash. One recent area of interest is the response of the neck during air bag loading. The biomechanical response of the Hybrid III dummy's neck was based on inertial loading during crash events, when the dummy is restrained by a seat belt and/or seat back. Contact loading resulting from an air bag was not considered when the Hybrid III dummy was designed. This paper considers the effect of air bag loading on the 5th percentile female Hybrid III dummies. The response of the neck is presented in comparison to currently accepted biomechanical corridors. The Hybrid III dummy neck was designed with primary emphasis on appropriate flexion and extension responses using the corridors proposed by Mertz and Patrick. They formulated the mechanical performance requirements of the neck as the relationship between the moment at the occipital condyles and the rotation of the head relative to the torso.

A new approach for improving estimates of the kinematic response of ATDs (anthropomorphic test devices) to vehicle crash events has been developed. This approach employs the Kalman Filter; a state model based estimation approach that has been widely applied to system dynamics problems ranging from navigation to missile guidance. The Kalman Filter approach combines measurements of crash event phenomena (acceleration and displacement), kinematic models of ATD behavior and statistics of sensor noise to create precise estimates of ATD motion during a crash. This paper presents an implementation of a state model and Kalman Filter for a sensor data collected from the chest of an ATD during an out-of-position airbag deployment test. Favorable comparisons are made between the Kalman Filter model approach and traditional methods involving numerical integration and differentiation.

This paper discusses a study conducted by GM to better understand the factors that influence injury potential in vehicle-to-vehicle side impacts. A number of other studies have been done which focus primarily on frontal vehicle-to-vehicle compatibility. GM focused on side impact compatibility in this study due to the risk of harm generally associated with this type of crash. Real world field performance was studied through an extensive six-state field analysis of recent model year (‘94+) vehicles. Of particular interest in this study was an efficacy analysis of the MVSS 214 dynamic side impact standard, which was phased-in starting with some 1994 model year passenger cars. Physical side impact crash testing of a 1997 passenger car was used to investigate the relationship of impacting mass, speed, geometric profile and stiffness on side impact intrusion and occupant injury.

Eight lateral dolly rollover tests were conducted on 1983 Chevrolet Malibusata nominal speed of 51.5 km/h (32 mi/h). Four of the vehicles had rollcages, and four had standard production roofs. Unrestrained outboard front GM Hybrid ill dummies with head and neck transducers were used. Numerous cameras documented the vehicle and dummy movements. Detailed vehicle kinematics data allowed quantitative analysis of the conditions for head and neck loads. For both roof structures, the dummies moved upward and outward from their seats due to rotation and acceleration of the vehicle. High head/neck loads were measured when the head contacted a part of the car experiencing a large change in velocity, often that part of the car which struck the ground. The results of this work indicate that roof strength is not an important factor in the mechanics of head/neck injuries in rollover collisions for unrestrained occupants.